First, we have to consider the element of time. It may well be true that all countries will end up the same in the long run. The problem is that we have no way of knowing how long this will take. We cannot simply look at the world today and say that countries will never become identical. All we can say is that they have not yet done so. For all we know, countries may eventually all be identical but it could take centuries for this to happen.

Second, we must consider how different various countries were when globalization started. Some countries were rather similar to one another when globalization began and are therefore rather similar today. For example, both the US and Australia were English-speaking, fairly wealthy, democratic countries with populations that were at least somewhat ethnically diverse. We should not be surprised that they are quite similar today. By contrast, the US and China were not very similar when globalization began. Therefore, we should not expect them to be identical today.

Finally, we must consider that this assumption might simply be wrong. There might be factors that will cause globalization to stall before it can make all countries identical. It might be that religion is too strong of a force to be overcome by globalization. Alternatively, we may find that countries are never willing to give up their own ways due to nationalism.

Overall, then, we cannot know for sure that globalization will eventually make all countries similar to one another. Even if it will eventually do so, it might simply not have had enough time to do its work.